Can Killifish Live With Bettas? 5 Tips To Keep Them Together

Many people do talk about the combination of Killifish and Betta fish, is it possible to keep two aggressive fish like these two in one tank? well, we will find out in a minute. Both fish are freshwater dwellers, and they are tropical fish too, so they share many things in common, such as level of aggression, similar water requirements, etc, little wonder why many people think they are a good combination, but the question is, are they?.

Can Killifish and Bettas live together? Yes, Killifish and Bettas can live together, but under some special conditions, if not, they will fight and kill each other.

Generally, it is not advisable to keep 2 aggressive animals in one tank, or, they will turn the tank into a battleground, and might harm or even kill one another in the process.

So, it is not advisable to keep these two different fish together, unless you know what you are doing, and you can handle them.

Although normally, they can’t be kept in the same tank, there are some tips, which might give you a chance to do that.

In this article, you will learn how to keep two of them together.

Tips To Keep Killifish And Bettas Together

1. Put in hiding places in their tank: One of the steps to limiting the level of aggression and fights in any tank is to introduce hiding places such as caves, pipes, substrates, etc, and also have the tank planted.

By so doing, the fish will be busy exploring and also hiding or staying away from each other’s way.

Once these are in place, even the rate of cannibalism on the fry will reduce too, as they will use those hiding places as Shelters and hideouts.

2. Get a very big tank for them: By far, this is the most important step to having a peaceful tank, despite keeping aggressive animals in it.

Naturally, a small tank is one of the factors responsible for breeding aggression in aquatic animals, which fish is among.

When the right tank size is introduced, both fish will have to keep to their territory and might avoid each other, at least to some level, thereby reducing aggression.

3. Keep more females than males: If you want to keep these two different fish together, then it is very necessary you keep more of their females than their males because both male Betta and male Killifish are very aggressive and territorial, they will fight for anything and nip at each other’s fins, etc.

So to control this to some extent, keep them at a ratio of 2-3 females per male, or better you keep only the females.

Although the females could become aggressive when they are pregnant, their level of aggression is very minimal compared to the males.

4. Divide the tank with a tank divider: If you are not very comfortable keeping them all in an open tank where they will interact with each other, you can still keep them in the same tank, but in different sections.

My point is, to get a big tank, then buy a tank divider and divide the tank, keeping each of them in their very own section, so that they won’t have access to come close to each other.

Honestly, this looks like the best way to go about this, as they will be in the same tank, but with zero aggression and fights.

5. Feed them in their different territories: When feeding them, feed them in their different territories and they won’t have to fight over food, because they do that a lot.

Both fish are Omnivores and could eat the same types of food, so be careful not to Overfeed them.

What To Do When Bettas Are Chasing Killifish, Or When They Fight.

Bettas are well-known fin and tail nippers, so are killifish, so at some point, the Bettas will start chasing the Killifish or the other way round.

When you notice this, you will simply have to tap on your aquarium and both will go into hiding.

Or use the option of tank divider and have peace forever in your tank.

The fact is like I mentioned above, it is not recommended to keep these two fish together, but you can do it with the help of the above tips, so with my tips, you can keep Bettas with any type of Killifish, be it Clown Killifish, Least Killifish, and even with the more peaceful Killifish, which is the Golden Wonder Killifish, etc.

To help you more, some of the fish that are compatible with each of these fish are:

Some of the possible suitable tank mates for Killifish



Large Tetras.


Banjo Catfish.


Some Fish you should avoid keeping with Betta fish unless you can handle them together are:

Other male Bettas.


Tiger Barbs.





Redtail sharks.

Angelfish, and so on.


Am not in any way directing you to keep killifish and Bettas in one tank, unless you are very knowledgeable about fish keeping, or you will use the tank divider method.

So, Killifish and Bettas are not suitable tank mates.